1. Field of the Invention
The present invention relates to the field of non-volatile integrated circuit analog signal recording and playback devices wherein an analog signal is directly stored in and read back from a storage cell.
2. Prior Art
Application Ser. No. 07/588,949 discloses a high density integrated circuit, analog signal recording and playback system wherein an analog input signal is sampled a plurality of times and then, as additional samples are being taken and temporarily held, a prior set of samples of the analog signal are simultaneously loaded into an equal plurality of storage sites or memory cells, preferably EEPROM cells. In that system the read process and circuitry connects each electrically alterable MOS storage device in a source follower configuration, which provides a one-to-one relationship between the variation of the floating gate storage charge (voltage) and the variation in the output voltage, with an insensitivity to load characteristics. That system's write process and circuitry provides a multi iterative programming technique wherein a series of coarse pulses program a cell to the approximate desired value, with a series of fine pulses referenced to the last coarse pulse being used for programming the respective cell in fine increments to a desired final programming level. The iterative write process is also disclosed in detail in application Ser. No. 07/636,879, with products generally in accordance with these disclosures being sold by Information Storage Devices, the assignee of the present invention, as its ISD1016 devices.